The importance that Competency-Based Training has today in Higher Education has led to the number of scholars on the subject increasing in recent years, being remarkable the number of articles on this area of knowledge found in various publications, generating the emergence of definitions and points of view that tend to create an epistemological situation that tends to create ambiguities, that in certain circumstances could create confusion in readers not familiar with the diversity of related topics. An aspect that should not be ignored by people who are interested in the study of Professional Competences, first from the conceptual and then its link with various spheres of knowledge, is the complex and polysemic character on which this context of science is developed.It is the specific purpose of this study to critically analyze this epistemological reality, around which many of the works on professional skills that deserve the attention of specialists from various branches of human knowledge.This work corresponds to the original version, in Spanish, published by Editorial EAE in 2017.